Two people have died, including a child, in a crash on Tasmania’s west coast.

Police said a red Honda all-terrain vehicle (ATV) had collided with a Mitsubishi Triton on the Murchison Hwy about 4.30pm on Saturday as it travelled between Zeehan and Rosebery.

A group of passing interstate tourists stopped to provide first aid before emergency services arrived.

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Despite their best efforts, the two victims — a 15-year-old girl from interstate and a 38-year-old Rosebery man — could not be saved.

The driver of the Mitsubishi, a 40-year-old man, was not physically injured and will be subject to mandatory drug and alcohol testing, police said.

“Tasmania Police would like to thank the group of interstate tourists who stopped and rendered medical assistance at the scene,” they said.

“Our thoughts are with the family and loved ones of both the deceased. A report will be prepared for the coroner.”

An investigation into the cause of the crash is underway.

Anyone with information in relation to the crash, or relevant dash cam footage that may assist, is asked to contact police.